[libcxx-commits] [libcxx] [libc++][memory_resource] Implements LWG3683. (PR #100775)

[Nikolas Klauser via libcxx-commits]

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@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14
+// TODO: Change to XFAIL once https://github.com/llvm/llvm-project/issues/40340 is fixed
+// UNSUPPORTED: availability-pmr-missing
+
+// <memory_resource>
+
+// template <class T> class polymorphic_allocator
+
+// friend bool operator==(const polymorphic_allocator& a,
+//                        const polymorphic_allocator& b) noexcept
+
+#include <memory_resource>
+#include <cassert>
+#include <vector>
+
+#include "test_macros.h"
+
+int main(int, char**) {
+  std::pmr::unsynchronized_pool_resource a;
+  std::pmr::vector<int> vec(&a);
+
+  assert(vec.get_allocator() == &a);
+  static_assert(noexcept(vec.get_allocator() == &a));
+
+#if _LIBCPP_VERSION || TEST_STD_VER >= 20
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philnik777 wrote:

libstdc++ and the MSVC STL also back-ported this to 17 the same way. Should we just add this test unconditionally?

https://github.com/llvm/llvm-project/pull/100775